The statements in this section merely provide background information related to the present disclosure and may not constitute prior art.
Internal combustions engines combust an air and fuel (A/F) mixture within cylinders to produce drive torque. More specifically, the combustion events reciprocally drive pistons that drive a crankshaft to provide torque output from the engine. The fuel is delivered to the engine by a fuel system. The fuel systems of some vehicles include a plurality of fuel tanks. For example, some fuel systems include a primary fuel tank and a secondary fuel tank that share a common filling neck.
The fuel levels within the fuel tanks are monitored and the vehicle operator is informed as to the amount of fuel remaining in each tank. More specifically, a fuel level sensor is provided in each tank. Each fuel level sensor is responsive to the fuel level in a respective tank and generates a signal based the fuel level. The amount of remaining fuel is determined based on the signals. Conventional fuel level monitoring systems include rationality diagnostics to determine whether the fuel level sensors are functioning properly.